Modular centrifuge devices and methods

ABSTRACT

A modular centrifuge device for separating fluid samples, including a housing having a modular power assembly mechanism for rotating samples with manual or electric power. A manual centrifuge device, including a housing having a power assembly mechanism for rotating samples with manual power, and a speed indicator for indicating if a predetermined speed has been reached and a time indicator for indicating if a predetermined or calculated time has been reached for rotating said samples operatively connected to the device. A method of centrifuging samples, by selecting a manual power mode or electric power mode on a centrifuge, rotating samples at a predetermined speed for a predetermined or calculated time, alerting a user that the predetermined speed and predetermined or calculated time have been achieved, and obtaining separated samples.

BACKGROUND OF THE INVENTION 1. Technical Field

The present invention relates to centrifuges for the separation ofbodily fluids. More specifically, the invention relates to manual powercentrifuges.

2. Background Art

Centrifuges generally work by spinning contained fluid samples at asufficiently high rate of rotational speed to cause separation of thefluids into their component parts by centrifugal force. Researchlaboratories and hospitals often use electrically powered centrifugesthat typically plug into a wall socket. These centrifuges are often verylarge and are not designed to be portable.

Known manually-powered centrifuges have a base that is clamped to astationary device, such as a table. A handle is mounted to the base andspins samples supported on a rotary wheel above the base. The standardtranslation of motion is through the handle driving a worm gear, whichdrives a worm, which then drives the rotary wheel and samples. The baseis generally narrower than the rotary wheel, and must be clamped to astationary device, such as a table, in order to provide balance for thebase and the spinning samples.

Standard manually-powered centrifuge designs have several drawbacks.Examples include Supertek, SYHD (a hand centrifuge by OEM), WhirlybirdCentrifuge, etc. These centrifuges list max speeds at 3,000 rpm, but thesustained speed is closer to 1,000. This means that the forces generatedare not high enough for all applications, for example, spinning blood topush red blood cells below a gel tube (such as BD VACUTAINER® SST™ andPST™ gel tubes) to ensure the sample does not remix during transportwould not work with these centrifuges. Also, the time required to usethese centrifuges is too much for comfortable use. They require about 10minutes to separate blood fully, which technicians (based on fieldfeedback) are unwilling to do. Applicants have heard from multiplelocations in India that previously had this type of centrifuge, andtechnicians reported that they were unwilling to spin the device forthis time. The technicians would just stop when they were tired, around2-4 minutes of spinning, and decide it was good enough. Thus, bloodsamples are not fully separated, leading to inaccurate test results.

These types of centrifuges do not have an indication of completion.Rural non-technical people in the developing world, or even ruraltechnicians, are not accustomed to using stopwatches and are unaware ofthe importance of maintaining a task for a specified amount of time. Onecannot rely on a rural minimally trained person to be able to timesomething with a watch/stopwatch for the proper time.

These centrifuges also lack safety. The tube holders spin openly, wherethey could be dangerous to anyone who sticks their finger in that area.This is a real consideration in rural and village areas: as said bydoctors who run a mobile clinic in India, “villagers tend to pokethings.” There is also no containment if a tube holder breaks. Thesedevices also have a c-clamp and therefore cannot be used without atable, which is unlikely to be available in a rural village setting.

The HANDYFUGE™ Plate Centrifuge (RPI) has a speed of 1,500 rpm/230 refobtained by pushing on a lever, and is specifically used for spinningdown PCR plates. This device does have an enclosure and can be used onany flat surface, but is ineffective for similar reasons of speed asaforementioned standard manual centrifuges due to insufficient forcesexerted on blood tubes. This device is also specifically tailored andmarketed only for PCR plates and is not designed to fit standard bloodtubes.

The Jabric manual centrifuge is able to reach high speeds of up to 5,000G's with a complete enclosure of the samples. However, there is noindication that this is the “useable” speed, and in reality is likelylower as described above. The Jabric centrifuge is also nearly $1,000,making it unlikely to be affordable in rural areas and third worldcountries. If they could afford this price, a village could buy anelectric generator and simply buy an electric centrifuge for around $50.

Multiple sources around the globe have come up with centrifuge designsout of readily available materials. These include a rural doctor inNigeria at the Awojobi Clinic Eruwa who created both a bicycle-based anda hand-drill based centrifuge that reach 5,400 and 4,410 rpm,respectively. College students and professors have tried to solve theproblem of a lack of an appropriate, affordable manual centrifuge bydesigning manual centrifuges out of salad spinners or egg beaters.Students at Rice University designed a salad-spinae based centrifugecalled the “sally centrifuge” that works for hematocrit only and onlyprovides about 200G force. An egg-beater based design reached 1,200 rpmor about 280 g-force (8 minutes of spinning required for complete plasmaseparation). These designs have not been successful due to issues withportability and commercial scalability.

Therefore, there remains a need for a centrifuge that is at acommercially affordable price (such as less than $200), has anindication of proper time and speed, does not require mounting to atable, is safe, and is able to operate with manual power at speedsrequired for complete blood separation in less than 4 minutes. There isalso a need for a centrifuge with the ability to alternate between useof manual and electric power

SUMMARY OF THE INVENTION

The present invention provides for a modular centrifuge device forseparating fluid samples, including a housing having a modular powerassembly mechanism for rotating samples with manual or electric power.

The present invention also provides for a manual centrifuge device,including a housing having a power assembly mechanism for rotatingsamples with manual power, and a speed indicator for indicating if apredetermined speed has been reached and a time indicator for indicatingif a predetermined or calculated time has been reached for rotating saidsamples operatively connected to the device.

The present invention also provides for a method of centrifugingsamples, by selecting a manual power mode or electric power mode on acentrifuge, rotating samples above a predetermined speed for apredetermined or a calculated time, alerting a user that thepredetermined speed and predetermined or calculated time have beenachieved, and obtaining separated samples.

DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention are readily appreciated as thesame becomes better understood by reference to the following detaileddescription when considered in connection with the accompanying drawingswherein:

FIG. 1 is a schematic side view illustration of a centrifuge deviceshowing components within a housing and base with hidden lines;

FIG. 2 is a schematic illustration in plan view of the centrifuge deviceof FIG. 1;

FIG. 3 is a schematic illustration in exploded perspective view of thecentrifuge device of FIGS. 1 and 2;

FIG. 4 is a schematic perspective illustration of an input shaft and agear assembly of the centrifuge device of FIGS. 1-3;

FIG. 5 is a schematic side view illustration of the input shaft and gearassembly of FIG. 4;

FIG. 6 is a schematic side view illustration of an alternate centrifugedevice showing components within a housing and base with hidden lines,and with a handle removed and replaced by an electrical power deviceincluding a motor and a battery;

FIG. 7 is a schematic side view illustration of another alternatecentrifuge device showing components within a housing and base withhidden lines, and with a handle removed and replaced by anotherelectrical power device including a motor and a wall plug;

FIG. 8 is a schematic side view illustration of another alternatecentrifuge device showing components within a housing and base withhidden lines, and with a handle removed and replaced by anotherelectrical power device including a motor and a solar panel;

FIG. 9 is a schematic side view illustration of another alternatecentrifuge device showing components within a housing and base withhidden lines, and with a handle removed and replaced by foot powereddevice;

FIG. 10 is a schematic perspective illustration of the centrifuge deviceof FIG. 1 showing an access door partially open and showing componentswithin a housing and base with hidden lines;

FIG. 11 is a schematic front view illustration of the centrifuge deviceof FIG. 1 showing components within a housing and base with hiddenlines;

FIG. 12 is a schematic back view illustration of the centrifuge deviceof FIG. 1 showing components within a housing and base with hiddenlines;

FIG. 13 is a schematic side view illustration of a centrifuge devicewith an alternate handle and showing components within a housing andbase with hidden lines; and

FIG. 14 is a cross-sectional view of the centrifuge device with spurgears.

DETAILED DESCRIPTION OF THE INVENTION

The present invention generally provides for a modular centrifuge devicefor separating fluid samples by either manual or electric power andmethods of use thereof. The centrifuge device includes a housing with amodular power assembly mechanism for rotating samples with manual orelectric power. Preferably, the samples are positioned at a bottom ofthe housing.

More specifically, referring to the drawings, wherein like referencenumbers refer to like components throughout the several views, FIG. 1shows a centrifuge device 10. As described herein, the centrifuge device10 is adaptable to allow an initial generation of motion to be by manualpower (i.e., hand powered), as shown, or to be powered by other methodssuch as by foot, or by electrical power received from a socket, from asolar panel, or from a battery (i.e. from an electrical power source).The centrifuge device 10 also includes an advantageous gear assembly 12and a relatively large base 14 configured to be at the bottom 15 of thecentrifuge device 10 during use.

The base 14 encloses sample containers 16 that hold bodily fluids to beseparated. The position of the sample containers 16 near the bottom 15of the centrifuge device 10, in the base 14, allows for increasedstability and enables the centrifuge device 10 to be used on anyrelatively flat surface, rather than requiring that the centrifugedevice 10 be clamped to a table or other stationary member. For example,the base 14 of the centrifuge device 10 can rest directly on the groundduring operation in a free standing manner. The centrifuge device 10 canalso rest in a free standing manner on a hood, or in a bed or cab of avehicle during operation. The bottom 15 (shown in FIG. 14) of the base14 can also be removable for easy access for cleaning, and can besecured with screws or any other suitable mechanisms. The base 14 canalso optionally include open areas, such as at the bottom 15 or portionsof the top.

As shown in FIG. 1, the centrifuge device 10 includes a handle 18 thathas a lever arm 20 and a grip 22 connected to the lever arm 20. Thelever arm 20 is connected to rotate in unison with an input shaft 24.Accordingly, when an operator holds the grip 22 and manually turns thehandle 18 about a first axis of rotation 26, the input shaft 24 rotatesabout the first axis of rotation 26. Thus, a manual source of power canprovide the initial generation of motion of the input shaft 24. Thehandle 18 can be rotated by a user horizontally or vertically, dependingon the design and placement of the gear assembly 12.

The input shaft 24 extends through an opening 25 in a housing 27 thatcontains the gear assembly 12. The gear assembly 12 operatively connectsthe input shaft 24 to a rotatable sample carrier member 28. Therotatable sample carrier member 28 has a plurality of holders 30, eachof which secures one of the sample containers 16 to the sample carriermember 28. The rotational motion of the input shaft 24 is transferredthrough the gear assembly 12 to rotate the rotatable sample carriermember 28. The containers 16 can contain bodily fluid that is separatedinto component parts by centrifugation due to the rotation of therotatable sample carrier member 28. When the sample carrier member 28 isrotated, the holders 30 with the sample containers 16 swing out at anangle towards the horizontal axis from the vertical axis starting pointat which the containers 16 are at rest. Preferably, the angle is from 45to 89 degrees in order to use less space within the base unit 14, andmore preferably, 80 to 89 degrees; however, other angles can also beused. The angle preferred can depend on the speed at which the holders30 are rotated, and at higher speeds, higher angles can be preferred.

As can be seen in FIG. 3, there are the six holders 30 in whichcontainers 16 with samples of bodily fluid can be placed for separation;however, a different number of holders 30 can be used, such as 2, 4, 6,8, or any other suitable number, to allow another number of samplecontainers 16 to be centrifuged at one time. The holders 30 and thesample carrier member 28 can be removed for cleaning. The holders 30 canalso accommodate multiple sample container 16 sizes with a snap-indesign. Holders 30 can also accommodate racks of sample containers 16.Any of the sample containers 16 or racks can be inserted or removedthrough access door 60 described below. Use of racks makes it easier toinsert sample container 16 opposite each other when desired. Colorcoding of opposite sample containers 16 and/or holders 30 can further beused to facilitate easy insertion at the proper opposite sides of thesample carrier member 28 to ensure balance in the centrifuge duringrotation. The holders 30 can further accommodate existing samplecontainers 16 that are used in existing electric centrifuges. Theholders 30 also allow the sample containers 16 to be removed withforceps when users are unable to wear gloves.

The samples of bodily fluid can be any or all of blood, plasma, urine,sputum, spinal fluid, and saliva, or any other bodily fluid.

The input shaft 24, gear assembly 12, and handle 18 can be referred toas a power transfer assembly 23 that enables the rotational motion ofthe handle 18 to cause rotational motion of the sample carrier member28, which thereby separates the bodily fluids in the containers 16 intotheir components by centrifugation. The power transfer assembly 23 isoperatively connected to the sample carrier member 28.

Alternate views of the centrifuge device 10 are shown in FIGS. 2 and 3.FIG. 2 shows a plan view of the centrifuge device 10 and FIG. 3 shows anexploded perspective view of the centrifuge device 10. It is apparentfrom FIG. 3 that the housing 27 and the base 14 are each formed in twohalves. The housing 27 can be integrally formed with the base 14. Thetwo halves of the housing 27 and base 14 connect to one another byfasteners that extend through openings 29 in the base 14. The housing 27can be configured differently than shown, but the base 14 remains belowthe housing 27. An access door 60 can slide to an open position via apeg 61 to allow insertion and removal of the containers 16. The accessdoor 60 is shown partially open in FIG. 10. As shown in FIG. 3, theaccess door 60 has two portions that cover two access openings 68 in thebase 14.

The centrifuge device 10 can be powered by a different input powersource by removing the handle 18 from the input shaft 24. The inputshaft 24 is adapted to be operatively connected to another power inputdevice, which generates the rotational motion of the input shaft 24 thatdrives the gear assembly 12. In FIG. 3, the handle 18 can disconnectfrom the input shaft 24 to be replaced by another power input device asdescribed herein to allow other means of generating rotational motionthat is transmitted through the gear assembly 12 to the sample carriermember 28, resulting in bodily fluid separation in the containers 16.

Specifically, an end of the arm 20 has recesses 32 and a central slot34. The input shaft 24 fits into the slot 34. A roll pin 21 that isdriven into the input shaft 24 rests against the arm 20 within therecesses 32 during operation. The handle 18 can be removed from theinput shaft 24 by moving it away from the slot 34. The handle 18 canthus be replaced with another power input device to generate rotationalmotion of the input shaft 24 as long as the portion of the power inputdevice configured to connect to the input shaft 24 has a shape similarto the end of the arm 20 (i.e., has a shape with recesses 32 and slot34), or another complementary shape that allows the power input deviceto be retained to the input shaft 24. This option for modularity enablesthe centrifuge device 10 to be used in a variety of environments inwhich different forms of input energy are available. The centrifugedevice 10 is a hybrid device that can be powered by human power (i.e.manually or by foot), or can selectively be electrically powereddepending on the power input device used.

FIG. 6 shows a modified centrifuge device 10A in which the handle 18 ofcentrifuge device 10 is removed, and an electrical power device 40 isinstead used as a power input device to provide rotational motion of theinput shaft 24. Specifically, the electrical power device 40 includes anelectric motor (M) 42 powered by stored energy in a battery (B) 44 torotate the input shaft 24 when a switch 46 is triggered. An adapter 20Awith a similar shape as the end of arm 20 (i.e., with recesses 32 andslot 34) fits to the input shaft 24 and the roll pin 21.

FIG. 7 shows another modified centrifuge device 10B in which the handle18 of centrifuge device 10 is removed, and an electrical power device140 is instead used as a power input device to provide rotational motionof the input shaft 24. Specifically, the electrical power device 140includes an electric motor (M) 142 powered by electrical power providedwhen a plug 143 is plugged into a wall socket. An adapter 20B with asimilar shape as the end of arm 20 (i.e., with recesses 32 and slot 34)fits to the input shaft 24 and the roll pin 21.

FIG. 8 shows another modified centrifuge device 100 in which the handle18 of centrifuge device 10 is removed, and an electrical power device240 is instead used as a power input device to provide rotational motionof the input shaft 24. Specifically, the electrical power device 240includes an electric motor (M) 242 powered by electrical energyconverted from solar power by a solar panel 244 with solar cells when aswitch 246 is triggered. An adapter 200 with a similar shape as the endof arm 20 (i.e., with recesses 32 and slot 34) fits to the input shaft24 and the roll pin 21.

One advantage of the electrical power device 40 and 140 of FIGS. 6-7 isthe ability to maintain the speed of the motor 42 or 142 at a constantspeed due to the constant level of power provided from the battery 44,or from the power source through the plug 143. This leads to a constantspeed of rotation of the input shaft 24, and a constant speed ofrotation of the sample carrier member 28, which is a higher speed thanthe speed of rotation of the input shaft 24 due to the gear assembly 12.

FIG. 9 shows another modified centrifuge device 10D in which the handle18 of centrifuge device 10 is removed, and a foot powered device 340 isinstead connected to the input shaft 24 to provide rotational motion ofthe input shaft 24. Specifically, the foot powered device 340 includestorque transfer device 342 such as a lever, pulley, or rope that ismounted to the input shaft 24 and having a foot pedal 344. Pumping ofthe foot pedal 344 transfers torque to the input shaft 24 to causerotation of the input shaft 24 through an adapter 200 in a similarmanner as a pedal for a spinning wheel. The adapter 20D has a similarshape as the end of arm 20 (i.e., with recesses 32 and slot 34) so thatif fits to the input shaft 24 and the roll pin 21.

Referring again to FIG. 1, the power transfer assembly 23 includes theinput shaft 24, the gear assembly 12, and the power input device, whichin the embodiment shown is the handle 18 but can instead be any of thepower input devices of FIGS. 6-9. The gear assembly 12 converts theinitial generation of rotational motion of the input shaft 24 into therotational motion of the sample carrier member 28 and the containers 16of bodily fluid supported thereon, resulting in the separation of thebodily fluid into its component parts. The gear assembly 12 multipliesthe rotational speed of the sample carrier member 28 relative torotational speed of the input shaft.

FIGS. 4 and 5 show different views of the gear assembly 12 including afirst gear, which is a large spur gear 50, mounted to rotate in unisonwith the input shaft 24 about the first axis of rotation 26. The gearassembly 12 further includes a smaller second gear, referred to as aspur gear 52, which is supported on a second shaft 53. The spur gear 52meshes with and is driven by the large spur gear 50. Another relativelylarge gear, referred to as a worm gear 54, is mounted to rotate on thesecond shaft 53 in unison with (i.e., at the same speed as) the spurgear 52. The second shaft 53, the spur gear 52 and the worm gear 54rotate about a second axis of rotation 57. A worm 56 with spiral cutteeth is mounted on a third shaft 58 and engages the worm gear 54. Thethird shaft 58 and the worm 56 rotate about a third axis of rotation 59.The rotatable carrier member 28 is mounted on the third shaft 58 torotate with the third shaft 58. FIG. 3 shows a central mount 62 in thecarrier member 28 that has an opening 64 configured to receive the thirdshaft 58. A screw can be extended through an opening 66 in the centralmount 62 and tightened against the shaft 58 within the mount 62 so thatthe central mount 62 and the entire carrier member 28 will rotate inunison with the third shaft 58. The end of the third shaft 58 rests on aball bearing 63 that is positioned on the base 14 to allow the thirdshaft 58 and worm 56 to rotate with minimal friction relative to thebase 14. In other words, the sample carrier member 28 is supported bythe base 14 through a friction minimizing device, which can be the ballbearing 63 or any other suitable device. Any of the motors (M) describedherein can also be directly connected to the third shaft 58 so that themotors (M) directly turn the sample carrier member 28 and the containers16 of bodily fluid, instead of turning the various gears describedabove. Alternatively, when a motor (M) is added to the device 10, thegear assembly 12 can be replaced with one specifically designed for themotor (M). Also, any or all of the worm gears described above can bereplaced with spur gears (generally shown at 51) so as to not have aplane change, such as in FIG. 14. In this case, all three shafts arerotated by spur gears 51. Also, the gear assembly 12 can be configuredto include more or fewer shafts in order to rotate the sample carriermember 28. In another alternative, the gear assembly 12 can be replacedwith a belt system or assembly.

FIGS. 10, 11, and 12 show additional views of the centrifuge device 10.It is apparent in FIGS. 10, 11, and 12 that the two halves of thehousing 27 can have openings at which the input shaft 24 and a centralportion of the second shaft 53 are rotatably supported. These openingsinclude the opening 25 through which the input shaft 24 extends toconnect with the handle 18 or other power input device, as well asopenings 25A, 25B, and 250.

FIG. 13 shows an alternate centrifuge device 10E alike in all aspects ascentrifuge device 10 of FIG. 1 except that the handle 18 is replacedwith an alternate handle 18A that has an arm 20A with a portion thatextends downward at a right angle to the input shaft 24.

Accordingly, in the gear assembly 12, the input shaft 24 drives the spurgear 50, which in turn drives the spur gear 52 and worm gear 54. Theworm gear 54 meshes with and drives the worm 56 and the sample carriermember 28. The sample carrier member 28 can be operatively connected torotate in unison with the worm 56. The worm gear 54 and the worm 56 areconfigured with a gear ratio causing an increase in rotational speed ofthe worm 56 relative to the worm gear 54. In one embodiment, the spurgear 50 has 60 teeth, spur gear 52 has 9 teeth, and the tooth ratio ofthe worm gear 54 to the worm 56 is 12.5:1. The tooth counts and toothratios of the gears 50, 52, 54, 56 can generate rotational speeds of thecarrier member 24 and the containers 16 of bodily fluids of over 3000revolutions per minute (rpm), and a relative centrifugal force (RCF) of2000 Gs. These numbers are based upon the assumption that the initialgeneration of motion at the input shaft 24 occurs at a standardrotational speed of 45 rpm; that is, the speed of the input shaft 24 is45 rpm. It is relevant to note that relative centrifugal force (RCF) forthe centrifuge device 10 of FIG. 1 is a function of the rotational speed(rpm) squared times the radius r of the sample carrier member 28 fromthe center of the sample carrier member 28 to the furthest (mostradially outward) tip of the container holder 30 shown in FIG. 1. Thestandard formula for RCF is (1.11824*10-5)*r*RPM2, where r is the radiusin centimeters of the sample carrier member 28 as described herein, andRPM is the rotational speed of the sample carrier member 28 inrevolutions per minute (and of the worm 56 and third shaft 58). Thenumber of teeth on each gear 50, 52, 54, or the radius r of therotatable sample carrier 28 could be adjusted to either increase ordecrease the RCF. One example of use of the device 10 is to turn thehandle 18 at 45 rpm for 3.5 minutes. It should be understood that therotational speed of the handle 18 is the same as the rotational speed ofthe input shaft 24.

FIG. 14 shows an alternate configuration of the centrifuge device 10wherein only spur gears 51 are used to drive the sample carrier 28, andno worm gears are used. In this configuration, the housing 27 is locatedon top of the base unit 14, and the handle 18 is operatively attached tothe top of the housing 27 instead of on the side as in the previousFIGURES. Thus, rotation occurs in a horizontal plane instead of avertical plane. For modularity, the handle 18 can be pressed down inorder to engage the gears, and can be pulled up to engage a motor (whichcan also be located within the housing 27). In this way, the device 10can easily switch between manual power and electric power and the handle18 can be toggled to select manual or electric power.

The centrifuge device 10 can include a speed indicator featureoperatively connected to the sample carrier member 28 and operable toindicate if the rotational speed of the carrier member 28 has reached apredetermined speed. Alternatively, the speed indicator feature can belocated at any suitable part of the centrifuge device 10, such as, butnot limited to, a gear or a shaft, and a calculation can be performed todetermine or predict the speed of the sample carrier member 28. Thepredetermined speed can be the speed required to generate the propercentrifugal force to cause separation of the bodily fluids in adesignated amount of time in the containers 16. In one embodiment, thespeed indicator feature can be a light that is powered by the rotationalmotion of the gear assembly 12 and is configured to require apredetermined amount of current to illuminate. The predetermined amountof current can be that amount generated via rotation of the samplecarrier member 28 at the predetermined speed. In other words the lightturns on once the predetermined speed is reached. The centrifuge device10 can also include a time indicator operatively connected to the samplecarrier member 28 (or any other suitable place) and the speed indicatorfeature. The time indicator indicates that the centrifuge device 10 hasbeen spun at the predetermined speed for a predetermined or calculatedtime. The time indicator can optionally calculate the input speed anduse that calculation to determine the needed time to separation of thesamples. The time indicator can also display the amount of time neededat that particular input speed to operate the centrifuge device 10 inorder to separate the samples. The time indicator can turn on or changecolor once the predetermined or calculated time has been reached whenrotation is occurring above or at the predetermined speed. The timeindicator can also be a light, and can be a different color than thespeed indicator or the same color. For example, the speed indicator canbe red and the time indicator can be green, or the speed indicator andthe time indicator can be green. The speed and time indicators can belocated anywhere appropriate on the device 10, such as on the housing27.

For example, referring to FIG. 1, a small generator of electricity G canbe mounted inside the housing 27 to the third shaft 58 or to anotherrotating member. The generator G can power a microcontroller thatanalyzes the speed of the rotating body it is measuring (i.e. any of theshafts, gears, belts, sample carrier member 28, etc. as described above)in order to determine and indicate the speed of the sample carriermember 28 and containers 16. The microcontroller can use thiscalculation to further determine the amount of time required to separatethe sample as described above. Most preferably, the generator G is abattery. Alternatively, the generator G can include a coil C thatrotates with the third shaft 58 and a magnet Mg mounted to the inside ofthe housing 27 so that it is positioned around the coil C within thehousing 27. Alternatively, the magnet Mg can be mounted to rotate withthe third shaft 58 or with another rotating member of the centrifugedevice 10, and the coil C can be mounted to a stationary (non-rotating)member, such as the housing 27. A light L is connected to the coil Cwhich carries a current due to magnetic flux and electromotive forceproduced when the third shaft 58 rotates, causing the light L toilluminate when sufficient current is generated. To ensure that thelight L illuminates only when the predetermined rotational speed isachieved or exceeded, an external resistor R is connected in series withthe light L. Therefore, the light L will illuminate only when greaterthan a particular predetermined voltage drop occurs across the light L.Because the resistance of resistor R is constant, the voltage drop is afunction of current which is ultimately a function of rotational speed.Although shown only on centrifuge device 10, the generator G with coil Cand magnet Mg and the light L can be used on any of the embodimentsdescribed herein.

Furthermore, the speed and/or time indictor feature can instead be acontrol sample of fluid in one of the containers 16 that can mimic theseparation of the bodily fluid and is known to separate into componentswhen a predetermined centrifugal force has been applied for apredetermined amount of time. The control sample can be periodicallyvisually checked to determine whether sufficient processing has occurredto achieve proper separation of the test samples in the containers 16.The speed and/or time indicator feature can also be any other suitablemechanisms that provide an alert at a predetermined speed and/or apredetermined or calculated time, such as, but not limited to, soundalerts (i.e. beeping), or moving/mechanical alerts (i.e. a “jack in thebox” where an indicator pops up from a resting state). The centrifugedevice 10 can also include additional alerts in a type described above,such as, but not limited to, when access door 60 has been left open.

Once the centrifuge device 10 has been operated at or above thepredetermined speed and the predetermined or calculated time, it isessential that the sample containers 16 slow down gradually so as not toremix the sample therein. Therefore, the centrifuge device 10 caninclude any appropriate slowing mechanism that slows down the rotationof the gears (and thus rotation of the sample container member 28 andcontainers 16) gradually once operation (whether manual or electric) hasstopped.

The present invention also provides more specifically for a manualcentrifuge device as described above, including a housing having a powerassembly mechanism for rotating samples with manual power, and a speedindicator for indicating if a predetermined speed has been reached and atime indicator for indicating if a predetermined or calculated time hasbeen reached for rotating said samples operatively connected to thedevice. Each of these parts have been described above.

Most generally, the present invention provides for a method ofcentrifuging samples, by optionally selecting a manual or electric powermode on a centrifuge, rotating samples at a predetermined speed for apredetermined or calculated time, alerting a user that the predeterminedspeed and predetermined or calculated time have been achieved, andobtaining separated samples.

More specifically, the user first adds samples to the sample containersand the sample containers are then inserted in the sample carrier memberat the bottom portion of the centrifuge. The user balances thecontainers if necessary within the sample carrier member. The accessdoor is closed. The user can select to use either manual power ofelectric power in order to rotate the input shaft in order torotate/spin the sample carrier member. Alternatively, if the modulardevice is not being used but rather the manual device, no selection isneeded. The centrifuge device can also easily be switched between manualand electric power by replacing the handle (or toggling the handle toengage) with an electrical power source to drive the input shaft. In themanual powermode, the user turns the handle (or operates the foot pump)at an appropriate speed for an appropriate time to separate the sampleswithin the containers. The handle essentially drives the input shaft andgear assembly to spin the sample carrier member. Preferably, the userturns the handle at 35 rpm for 3.5 minutes, but any other suitable speedand time can be used. Once the predetermined speed has been reached, thespeed indicator can turn on as described above. Once the predeterminedor calculated time at that speed has been reached, the time indicatorcan also turn on as described above. The user stops turning the handleor the electric motor stops and the rotation of the sample carriermember with the samples can gradually slow down. The access door can beopened and the containers with the separated samples removed from thesample container. At this point, further tests can be performed on theseparated samples, such as, but not limited to, dengue fever, syphilis,typhoid fever, diabetes, HIV, malaria, etc.

The centrifuge device of the present invention has several criticaladvantages over prior art manual centrifuges. The centrifuge device is amodular device and is able to be easily operated with either manualpower or electric power when available. This saves rural clinics moneybecause they do not have to buy a separate device for when or if theyhave electric power available. There is a complete enclosure of thesamples within the centrifuge, so that the centrifuge device can operatesafely in environments where people are not used to such devices. Thecentrifuge device is able to operate at high enough speeds (i.e. 2000rpm or more) to effectively separate samples of bodily fluid, andespecially blood or plasma. This speed is able to be achieved even withmanual power. The centrifuge device is designed to not require clampingto any object but rather is free standing. In order to accomplish this,the gears are positioned at the top of the centrifuge device whereas thesample container is positioned at the bottom. The centrifuge deviceincludes light indicators that easily show an operator that the correctspeed and time have been achieved for spinning samples. Furthermore,because of the speed that the centrifuge device is able to operate at,the time required to spin samples is much less than previous manuallypowered devices. This ensures that the centrifuge device is usedproperly in a rural village setting.

The invention is further described in detail by reference to thefollowing experimental examples. These examples are provided for thepurpose of illustration only, and are not intended to be limiting unlessotherwise specified. Thus, the invention should in no way be construedas being limited to the following examples, but rather, should beconstrued to encompass any and all variations which become evident as aresult of the teaching provided herein.

EXAMPLE 1

Use case 1: Mobile Clinic: The need and specifications for thecentrifuge device were developed through observation and travelling witha mobile clinic in the areas around Sargur, India. In this setting,diagnostic equipment was limited to a stethoscope. If a seriouscondition, such as Typhoid Fever, was suspected, a blood sample would bedrawn and transported back to the main lab if they could get it backwhile the blood was still accurate for diagnostic tests. According toblood lab technicians in India, whole blood at room temperature is onlygood for 3 hours for most tests, but plasma is good for up to 3 days. Atthe lab they would centrifuge the blood and run a Rapid Diagnostic Test(RDT). Simply the presence of a device such as the present inventionwould allow immediate blood separation, testing with an ROT anddiagnosis on location. The Swami Vivekananda Youth Movement (SVYM)expressed interest in purchasing a device such as the invention fortheir mobile clinic for this reason. SVYM was aware of the existingstandard manual centrifuge design. They cited reasons for insufficientspeed, too much time required for blood separation and the device'sreliance on a stopwatch to know when the sample was fully separated. Thelong amount of time to separate blood and poor ergonomics made thestandard manual centrifuge unpopular and most people did not want to useit. The requirement of a person using the centrifuge to be reliant on astopwatch was an issue because the person operating the centrifuge oftenhad limited training and education, meaning that using a stopwatch wasnot intuitive or a standard part of their culture; therefore, the devicewas used improperly and not spun for the proper time, leading toinaccurate test results.

Use case 2: Pregnancy clinic: In Karnataka, India, Applicants witnesseda pregnancy clinic for expecting mothers. A doctor and a phlebotomistwere driven to a village schoolhouse where the pregnant women of thecommunity had been told to attend. The doctor brought equipmentcomprised of a stethoscope, scale, electric centrifuge, syringe, andnon-electric diagnostic tests with them to the village. Applicants saweach pregnant woman go through prenatal testing including having theirblood drawn, separating the blood using the electric centrifuge, andthen having a battery of tests run to test the expectant mother'shealth. Applicants were told by a doctor and administrator of theorganization that ran the pregnancy clinic that the clinic was relianton the electric centrifuge and therefore reliant on the presence ofelectricity. Applicants were told that 40% of the time the doctor andphlebotomist would arrive for the pregnancy clinic only to cancel theclinic because there was a power cut at that time and no electricity.Applicants were told that a device such as the present invention wouldbe ideal. The clinic wanted a device that could run on electricity whenit was present.

Use case 3: semi-urban clinic: In multiple urban and semi-urban clinicsout of Andhra Pradesh and Tamil Nadu, technicians and lab specialistsexpressed the need and desire for a device that could operate on bothmanual power and electricity. They cited India's frequent power cuts asthe driver behind the need for the device. Laboratories in these clinicshad an electric centrifuge, but when the power went out these deviceswere often inoperable. Some of these clinics had generators that wouldpower the centrifuge if the power went out; however, in some of theselocations the generators were insufficient due to the high powerrequirements of the electric centrifuge that the generator could notsustain. Some locations cited the high cost of generators that wererequired for the electric centrifuge they used as an issue. Multipleclinics expressed the need and willingness to pay for a centrifuge suchas the present invention that could use both electric power whenelectricity was available and manual power when electricity was notavailable.

Each of the above use cases demonstrate that the present inventionfulfills a long-felt need in the rural developing world communities thatprior centrifuges, whether manual or electric, have been unable tofulfill. The present invention provides significant advantages overprior art devices in that it is easy to use, provides clear indicationsof time and speed requirements for sample separation, and its modulardesign allows use with and without electricity.

Throughout this application, various publications, including UnitedStates patents, are referenced by author and year and patents by number.Full citations for the publications are listed below. The disclosures ofthese publications and patents in their entireties are herebyincorporated by reference into this application in order to more fullydescribe the state of the art to which this invention pertains.

The invention has been described in an illustrative manner, and it is tobe understood that the terminology, which has been used is intended tobe in the nature of words of description rather than of limitation.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims, the inventioncan be practiced otherwise than as specifically described.

1-25. (canceled)
 26. A centrifuge device for separating fluid samples,comprising: a base; a housing coupled to a top portion of the base; arotatable sample carrier having a holder configured to securably hold asample container, the rotatable sample carrier being enclosed in thebase; a power transfer assembly comprising: an input shaft coupled tothe rotatable sample carrier such that the rotatable sample carrier isconfigured to rotate in unison with the input shaft, a manual powersource, and an electric power source; and a handle coupled to the inputshaft, wherein the handle is configured to be toggled between a firstposition in which the input shaft is engaged with the manual powersource and a second position in which the input shaft is engaged withthe electric power source to thereby rotate the rotatable samplecarrier.
 27. The centrifuge device of claim 26, wherein the centrifugedevice is free-standing.
 28. The centrifuge device of claim 26, whereinthe centrifuge device is comprised of modular components.
 29. Thecentrifuge device of claim 26, wherein the manual power assemblycomprises a gear assembly or a belt assembly.
 30. The centrifuge deviceof claim 29, wherein the gear assembly comprises a plurality of gearsconfigured to multiply a rotational speed of the input shaft relative toa rotational speed of the handle.
 31. The centrifuge device of claim 26,wherein the base includes an access door for accessing the rotatablesample carrier.
 32. The centrifuge device of claim 26, wherein therotatable sample carrier comprises a plurality of holders configured toswing outward at an angle when rotated.
 33. The centrifuge device ofclaim 32, wherein the angle is between 45 to 89 degrees from a verticalaxis when rotated.
 34. The centrifuge device of claim 26, wherein thehousing further encloses the power assembly.
 35. The centrifuge deviceof claim 26, wherein the sample container is chosen from the groupconsisting of: a snap in sample container and a rack of samplecontainers.
 36. The centrifuge device of claim 26, wherein the basefurther comprises a removable bottom.
 37. The centrifuge device of claim26, wherein a rotation of the handle occurs in a horizontal planeinstead of a vertical plane.
 38. The centrifuge device of claim 26,further comprising a speed indicator operatively connected to therotatable sample carrier and configured to indicate whether a rotationalspeed of the rotatable sample carrier has reached a predetermined speed.39. The centrifuge device of claim 38, further comprising a timeindicator operatively connected to the rotatable sample carrier and thespeed indicator, wherein the time indicator is configured to indicatethat the rotatable sample carrier has been spun at the predeterminedspeed for a predetermined or calculated time.
 40. The centrifuge deviceof claim 38, wherein the speed indicator comprises a light thatconfigured to require a predetermined amount of current to illuminate.